Carrier 58TMA - Adaptive Heating Mode; Non-Adaptive Heating Mode

This furnace is equipped with 2 manual reset limit switches in
the gas control area. The switches will open and shut off
power to the gas valve if a flame rollout or an overheating
condition occurs in the gas control area. DO NOT bypass the
switches. Correct inadequate combustion air supply, compo-
nent failure, restricted flue gas passageway before resetting
switches.
SEQUENCE OF OPERATION
Using the schematic diagram follow the sequence of operation
through the different modes. (See Fig. 15.) Read and follow the
wiring diagram very carefully.
NOTE: If a power interruption occurs during a "call for heat"
(W/W1 or W/W1-and-W2), the control starts a 90-sec blower only
on period 2 sec after power is restored if the thermostat is still
calling for gas heating. The red LED flashes code 12 during the
90-sec period, after which the LED will be on continuously as long
as no faults are detected. After the 90-sec period, the furnace
responds to the thermostat normally.
The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
control CPU, transformer TRAN, inducer motor IDM, blower
motor BLWM, hot surface ignitor HSI, and gas valve GV.
1. Adaptive Heating Mode—Single-Stage Thermostat and
2-Stage Heating
(See Fig. 12 for thermostat connections.)
NOTE: With the high-heat-only switch SW-1 off, the low-heat-
only switch SW-2 selects either the low-heat-only operation mode
when on (see item 2. below), or the adaptive heating mode when
off in response to a "call for heat." (See Fig. 14.) When the
high-heat-only switch SW-1 is on, it always causes high-gas-heat
operation when the R-W/W1 circuit is closed, regardless of the
setting of the low-heat-only switch SW-2.
This furnace can operate as a 2-stage furnace with a single-
stage thermostat because the furnace control CPU includes a
programmed adaptive sequence of controlled operation which
selects low-gas-heat or high-gas-heat operation. This selection
is based upon the stored history of the length of previous gas
heating on/off periods of the single-stage thermostat.
The furnace starts up in either low- or high-gas heat. If the
furnace starts up in low-gas heat, the control CPU determines
Fig. 13—Heating and Cooling Application Diagram With 2-Stage Thermostat and Condensing Unit
A93379
115-VOLT FIELD-
SUPPLIED
FUSED
DISCONNECT
JUNCTION
BOX
CONTROL
BOX
24-VOLT
TERMINAL
BLOCK
THREE-WIRE
HEATING-
ONLY
SIX
WIRE
2-STAGE
THERMOSTAT
TERMINALS
FIELD-SUPPLIED
FUSED DISCONNECT
2-SPEED
CONDENSING
UNIT
FURNACE
G
R
W2 Y2 G Y1
GND
GND
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
NOTE: Connect Y-terminal as
 shown for proper
operation.
NOTE: If any of the original wire,
as supplied, must be replaced, use
same type or equivalent wire.
208/230- OR
460-VOLT
THREE
PHASE
208/230-
VOLT
SINGLE
PHASE
Y2
Y1
C
WHT
BLK
WHT
BLK
W1 R
W2
COM
W/W1
Y/Y2
Table 7—Blower Off Delay Setup Switch
Position
DESIRED HEATING
MODE BLOWER OFF
DELAY (SEC)
SETUP SWITCH
SW-3 SW-4
90 OFF OFF
135 OFF ON
180 ON OFF
225 ON ON
Fig. 14—Setup Switches on Control Center
(Factory Settings)
A93377
BLOWER-
OFF
DELAY
LOW
HEAT
(ADAPTIVE
ALOGRITHM)
ONLY
HIGH
HEAT
ON OFF
4
3
2
1
10